The OEIS is supported by the many generous donors to the OEIS Foundation.

 Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 60th year, we have over 367,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”). Other ways to Give
 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A204256 Permanent of the n-th principal submatrix of A204255. 2
 1, 3, 19, 86, 1060, 13276, 215308, 3086544, 68937280, 1552257216, 40750688448, 987692033664, 31883024335104, 1036810188322560, 37597332892066560, 1285416947916933120, 54309158991453634560, 2309262618253981040640, 106842526312699253145600 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Vaclav Kotesovec, Table of n, a(n) for n = 0..35 MATHEMATICA f[i_, j_] := 1 + Mod[i + j, 4]; m[n_] := Table[f[i, j], {i, 1, n}, {j, 1, n}] TableForm[m[8]] (* 8x8 principal submatrix *) Flatten[Table[f[i, n + 1 - i], {n, 1, 12}, {i, 1, n}]] (* A204255 *) Join[{1}, Table[Permanent[m[n]], {n, 1, 20}]] (* A204256 *) PROG (PARI) a(n) = matpermanent(matrix(n, n, i, j, 1 + ((i+j) % 4))); \\ Michel Marcus, Jan 30 2021 CROSSREFS Cf. A204255. Sequence in context: A163431 A167242 A089621 * A015528 A183384 A050863 Adjacent sequences: A204253 A204254 A204255 * A204257 A204258 A204259 KEYWORD nonn AUTHOR Clark Kimberling, Jan 14 2012 EXTENSIONS a(0) and a(18) from Pontus von Brömssen, Jan 30 2021 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 10 15:23 EST 2023. Contains 367713 sequences. (Running on oeis4.)